Apple has released the Mac OS X 10.5.5 Update via its Software Update utility and on the Web. According to the company, the 10.5.5 Update is recommended for all users running Mac OS X Leopard and includes general operating system fixes that enhance the stability, compatibility and security of your Mac. This includes the following improvements:

General
- Includes recent Apple security updates.
- Addresses stability issues with video playback, processor core idling, and remote disc sharing for MacBook Air.
- Addresses an issue in which some Macs could unexpectedly power on at the same time each day.
- Resolves a stability issue in TextEdit that could be found when accessing the color palette.
- Improves Spotlight indexing performance.
- Fixes an issue in which contacts might not sync properly with PalmOS-based devices.
- Improves iPhone sync reliability with iCal and Address Book.
- Includes improvements to Active Directory.
- Improves Speech Dictionary.
- Fixes Kerberos authentication issues for Mac OS X 10.5 clients that connect to certain Samba servers, such as Mac OS X Server version 10.4.
- Includes extensive graphics enhancements.

Address Book
- Addresses stability issues that may occur when creating a Smart Group.
- Resolves a printing issue with address cards containing information that spans more than one page.

iCal
- Updates iCal to more accurately handle repeating events.
- Improves performance when choosing meeting attendees.
- Resolves an issue in which the "Refresh All" option may be dimmed ("grayed out") in the contextual menu for certain calendars.
- Fixes issues with read-only calendars.
- Addresses an issue that prevents an invitee from moving an event to a different calendar.
-Resolves an issue with syncing published calendars.

Mail
- Addresses performance issues related to displaying IMAP messages.
- Resolves an issue with SMTP settings for AIM, Compuserve, Hanmail, Yahoo!, and Time Warner Road Runner email accounts.
- Addresses stability issues that may occur when dragging a file to the Mail icon in the Dock.
- Addresses an issue with the "Organized by Thread" view in which the date does not appear when the thread is collapsed.
- Resolves an issue in which RSS feeds could temporarily disappear from the sidebar.
- Improves Mail robustness when sending messages.
- Improves reliability when saving drafts that have attachments.

Time Machine
- Time Machine can now back up iPhone backups that are on your Mac, as well as other items in ~/Library/Application Support.
- Improves Time Machine reliability with Time Capsule.
- Addresses performance issues that may affect initial and in-progress backups.
- Fixes an issue in which an incorrect alert message could appear stating that a backup volume does not have enough free space.

The Mac OS X 10.5.5 Update weighs in at 316MB, and requires Mac OS X 10.5.4 or later. A Combo update for Mac OS X 10.5.5 is also available here.

I just installed the 10.5.5 update on my G4 Mac mini, but I'm going to hold off on updating the other two. At least until the next iTunes update comes out. Everything is just working so well together. I'm also having fun playing with my new toy. Who has the time? _________________1.25GHz Mac Mini / 1.8GHz iMac G5 / 2.0GHz C2D Mac mini (2009)
4GB iPod mini / 2G iPod shuffle / 16GB iPhone 3G
Apple TV 2
iLife's a Bitch!

The update was around 150mb for me, did a double restart as well but all seems to be working well._________________MacBook 1.83Ghz C2D, 2GB Ram, 160GB 7200rpm HDD, OS X 10.6.5
Harman Kardon Soundsticks II
Elgato EyeTV
iPhone 4 Black 16GB

I installed the big combo update on my Intel iMac after first repairing permissions. Everything seems fine except for one small thing. The Sync menubar item didn't work at first, and when I went to sync mobile me manually from the preference pane, it encountered a problem with the iCal portion of the sync. The sync of my addressbook also took a long time, but it was apparently OK. After doing the sync, my menubar sync works again, and a retry synced my calendar._________________Mini 1 (2012): 2.3 ghz Core i7; 10 gb RAM, Corsair 240gb SSD, 500 gb Seagate XT
Mini 2 (2009): 2.26 ghz Core 2 duo, 8 gb RAM, 500 gb Seagate used as HTPC
Also a 13" MacBook Air, 21.5" i5 iMac & 11.6" Acer 1810TZ running Ubuntu, openSUSE & Crunchbang

Warning: SUID file "System/Library/CoreServices/Finder.app/Contents/Resources/OwnerGroupTool" has been modified and will not be repaired.
Warning: SUID file "usr/bin/lppasswd" has been modified and will not be repaired.

Several people reported it on MacNN.com. At least one said it went away when they subsequently ran the combo installer. That's why I never do a system update from the Software Updater. You might want to try that combo and see what happens.

You are correct. It went away. The thing is, I knew better. This is the first update I have done through Software Update since about 10.4.1. I guess my excuse is my MacBook is less than a month old and I'm still a little "over-eager". Many thanks for the info._________________Mac Book 2.1 Ghz (Penryn) 10.7.5 4Gb DDR2
Mac Mini 2.3 Ghz Intel iG 10.10.2 8Gb DDR3
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